TUBE D'ECOULEMENT DOTE D'UNE TURBINE A EAU DE SECTION VARIABLE

FLOW PIPE COMPRISING A WATER TURBINE HAVING A VARIABLE CROSS-SECTION

Abrégé français

De manière générale, dans des centrales hydroélectriques, l'eau circule dans un tube avant de rencontrer la turbine de la centrale et de lui transmettre son énergie. En fonction du type de centrale hydroélectrique, ce tube peut être un tube de chute par lequel l'eau s'écoule en fonction des circonstances locales en dépendant de la hauteur de chute et de la quantité d'eau. L'invention a pour objet la mise au point de moyens permettant la régulation de la vitesses d'écoulement de l'eau (liquide) au niveau de la turbine. A cet effet, l'invention concerne un tube d'écoulement à l'intérieur duquel se trouve une turbine qui, lorsqu'un écoulement s'effectue dans le tube, est mise en rotation par un liquide, la turbine présentant une section variable grâce à laquelle la section d'écoulement à l'intérieur du tube peut être modifiée.

Abrégé anglais

It is generally known in relation to hydroelectric power stations that,
before the water impinges on the turbine of the hydroelectric power station
and there delivers its energy to the turbine, the water flows through a pipe.
Depending on the respective nature of the hydroelectric power station that
pipe can be a downpipe through which the water flows, according to the
respective local factors, in dependence on the fall height and the amount of
water.
Now, the object of the invention is to provide means, by which the
flow speed of the water (fluid) can be adjusted in the region of the turbine.
A flow pipe, within which is arranged a turbine which, when a fluid
flows through the pipe, is caused to rotate, wherein the turbine has a
variable cross-section, by means of which the through-flow cross-section
within the pipe is variable.

Revendications

Claims
1. A hydroelectric power station comprising:
a flow pipe; and
a turbine disposed within the flow pipe and caused to rotate when fluid flows
through the pipe, the turbine having an enlargeable cross-section to reduce a
cross
sectional area for through-flow of fluid within the flow pipe.
2. The hydroelectric power station of claim 1 wherein the enlargeable cross-
section comprises an enlargeable cross section to correspondingly reduce the
cross
sectional area for fluid flow.
3. The hydroelectric power station of claim 1 wherein the turbine comprises a
deformable bellows to enlarge the enlargeable cross section.
4. The hydroelectric power station of claim 3 wherein the deformable bellows
has
an elastic surface.
5. The hydroelectric power station of claim 4 wherein the deformable bellows
has
an interior to receive fluid having a pressure greater than a pressure outside
the de-
formable bellows.
6. The hydroelectric power station of claim 5 further comprising a generator
cou-
pled to the turbine, to convert kinetic energy into electrical energy.
7. The hydroelectric power station of claim 1 further comprising a generator
cou-
pled to the turbine, to convert kinetic energy into electrical energy.
8. The hydroelectric power station of claim 1 wherein the turbine comprises a
body and rotor blades mounted on the body.
9. The hydroelectric power station of claim 1 wherein the enlargeable cross-
section comprises an enlargeable cross section to reduce the cross sectional
area for
fluid flow providing in an increase in a flow speed of the fluid flowing
within the pipe
and an increase in a rotational speed of the turbine.
10. The hydroelectric power station of claim 1 wherein the turbine has a
plurality of
blades and the enlargeable cross-section comprises an enlargeable cross-
section in
the region of the plurality of blades.

11. The hydroelectric power station of claim 10 wherein the enlargeable cross-
section comprises an enlargeable cross section to correspondingly reduce the
cross
sectional area for fluid flow.
12. The hydroelectric power station of claim 10 wherein the turbine comprises
a
deformable bellows to enlarge the enlargeable cross section.
13. The hydroelectric power station of claim 12 wherein the deformable bellows
has an elastic surface.
14. The hydroelectric power station of claim 13 wherein the deformable bellows
has an interior to receive fluid having a pressure greater than a pressure
outside the
deformable bellows.
15. The hydroelectric power station of claim 14 further comprising a generator
coupled to the turbine, to convert kinetic energy into electrical energy.
16. The hydroelectric power station of claim 10 further comprising a generator
coupled to the turbine, to convert kinetic energy into electrical energy.
17. The hydroelectric power station of claim 10 wherein the turbine comprises
a
body and the plurality of blades comprises blades mounted on the body.
18. A method for use in association with a hydroelectric power station having
a
flow pipe, the method comprising: providing a turbine within the pipe to
receive ki-
netic energy when fluid flows through the pipe; and enlarging a cross-
sectional area
of the turbine to reduce a cross sectional area for fluid flowing within the
flow pipe.
19. The method of claim 18 further comprising converting the kinetic energy
into
electrical energy.
20. The method of claim 18 wherein enlarging the cross sectional area
comprises
enlarging the cross sectional area to increase a flow speed of the fluid
flowing within
the pipe to adjust a rotational speed of the turbine to a generator system.
21. The method of claim 18 wherein enlarging the cross sectional area
comprises
enlarging the cross sectional area to increase a flow speed of the fluid
flowing within
the pipe to increase a rotational speed of the turbine.

22. A system comprising: a flow pipe; and a turbine disposed within the flow
pipe
and caused to rotate when fluid flows through the pipe, the turbine having an
enlargeable cross-section to reduce a cross sectional area for through-flow of
fluid
within the flow pipe; and wherein the turbine comprises a deformable bellows
to
enlarge the enlargeable cross section.
23. The system of claim 22 wherein the deformable bellows has an elastic sur-
face.
24. The system of claim 23 wherein the deformable bellows has an interior to
re-
ceive fluid having a pressure greater than a pressure outside the deformable
bellows.
25. The system of claim 24 further comprising a generator coupled to the
turbine,
to convert kinetic energy into electrical energy.

Description

CA 02469074 2007-09-08
FLOW PIPE COMPRISING A WATER TURBINE HAVING A VARIABLE CROSS-SECTION
It is generally known in relation to hydroelectric power stations that,
before the water impinges on the turbine of the hydroelectric power station
and there delivers its energy to the turbine, the water flows through a pipe.
Depending on the respective nature of the hydroelectric power station that
io pipe can be a downpipe through which the water flows, according to the
respective local factors, in dependence on the fall height and the amount of
water.
After the water has delivered a part of its energy to the turbine, the
water further flows away into a river.
The turbine of the hydroelectric power station is usually coupled to a
generator, with which the kinetic energy of the turbine is converted into
electrical energy, the electrical energy then in turn being fed into a power
supply network.
Often a hydroelectric power station has not just one turbine but also
a plurality of turbines and the water is fed to various turbines not just by
way of a single pipe but by way of a plurality of pipes. Depending on the
respective amount of water arriving suitable control of the amount of water
for the individual pipes is then implemented so that an optimum degree of
efficiency is achieved in the hydroelectric power station.
The turbines are each arranged in the downpipe itself or in the
prolongation of the downpipe in the flow pipe.
The passage cross-section for the water in the downpipe, also in the
region of the turbine (water impeller) in the flow pipe is fixed in that case
at predetermined values.
The flow speed of the water in the region of the turbines is in this
case usually adjusted by the volume flow, that is to say by the amount of
water introduced in the downpipe or the flow pipe. Depending on the

CA 02469074 2006-10-11
2
respective generator moment which is set, it is then possible to take the
desired power
from the system.
Now, the object of the invention is to provide means, by which the flow speed
of
the water (fluid) can be adjusted in the region of the turbine.
According to the invention that object is attained by a flow pipe within which
is
arranged a turbine which, when a fluid flows through the pipe, is caused to
rotate, and in
which the turbine has an enlargeable cross-section, by means of which the
through-flow
cross-section within the pipe can be correspondingly reduced. In one
embodiment of
the invention, a hydroelectric power station is provided which has:
a flow pipe; and
a turbine disposed within the flow pipe and caused to rotate when fluid flows
through the pipe, the turbine having an enlargeable cross-section to reduce a
cross
sectional area for through-flow of fluid within the flow pipe.
According to the invention the turbine is so equipped that it has a variable
cross-
section.
As illustrated in the Figure the turbine 4 (water wheel) comprises a
displacement
body 1, on which the vanes 5 (rotor blades) of the turbine are mounted on the
outside
thereof. The turbine 4 with the vanes 5 can rotate in the flow pipe 3 and thus
drive a
suitably coupled generator (not shown in the Figure).
As can be seen in the illustrated example the cross-section of the
displacement
body is variable. For that purpose the displacement body 1 is in the manner of
a
bellows and is provided with an elastic surface. When now the bellows is
supplied from
the interior with a suitable pressure which is greater than the external
pressure in the
flow pipe, the bellows expands and assumes the shape indicated by the broken
line 2.
As the entire turbine is of a circular configuration and that also applies in
respect of the
bellows, the increased cross-sectional area of the displacement body
automatically
becomes a reduced cross-sectional area for the water within the flow pipe 3.

CA 02469074 2006-10-11
2A
That reduced cross-sectional flow area for the water in the flow pipe
automatically results in an increase in the flow speed so that the entire
turbine is driven
more rapidly than previously.
Expandability of the displacement body can be embodied by its elastic surface
and, to expand the bellows, it can be provided that a fluid is pumped into the
interior of
the flow body or the bellows.
Thus, by means of adjustment of the cross-section of the displacement body, it
is
also possible for the speed of rotation of the entire

CA 02469074 2004-06-02
3
turbine to be adapted to a desired value for the respective generator so
that the speed of rotation of the turbine is optimally adapted to the
generator system and thus the best possible degree of efficiency is also
achieved.
The measure set forth in accordance with the invention is extremely
simple and nonetheless at the same time highly effective.
The arrangement for arresting and mounting the turbine is not
shown in the Figure, for reasons of clarity thereof.

Dessin représentatif